World Congress on Biosensors 2014

World Congress on Biosensors 2014
Biosensors 2014

Friday, 9 September 2011

Just Published: Analytica Chimica Acta

A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:
Selected papers from the latest issue:

Development Of a Technique Based On Multi-Spectral Imaging For Monitoring The Conservation Of Cultural Heritage Objects

08 September 2011, 20:28:21Go to full article
Publication year: 2011
Source: Analytica Chimica Acta, In Press, Accepted Manuscript, Available online 7 September 2011
Emilio, Marengo , Marcello, Manfredi , Orfeo, Zerbinati , Elisa, Robotti , Eleonora, Mazzucco , ...
A new approach for monitoring the state of conservation of cultural heritage objects surfaces is being developed. The technique utilizes multi-spectral imaging, multivariate analysis and statistical process control theory for the automatic detection of a possible deterioration process, its localization and identification, and the wavelengths most sensitive to detecting this before the human eye can detect the damage or potential degradation changes occur. A series of virtual degradation analyses were performed on images of parchment in order to test the proposed algorithm in controlled conditions. The spectral image of a Dead Sea Scroll (DSS) parchment, IAA (Israel Antiquities Authority) inventory...

Graphical abstract

 Graphical abstract:  Highlights: ► We develop a new approach for the monitoring of cultural heritage objects. ► The technique uses multispectral imaging coupled with multivariate analysis. ► We tested the technique on simulated data and on a sample of parchment artificially aged. ► The technique detected the degraded area and the interested wavelengths even for small degradations.
image

PREDICTION OF COMPOSITIONAL AND SENSORY CHARACTERISTICS USING RGB DIGITAL IMAGES AND MULTIVARIATE CALIBRATION TECHNIQUES

08 September 2011, 20:28:21Go to full article
Publication year: 2011
Source: Analytica Chimica Acta, In Press, Accepted Manuscript, Available online 7 September 2011
G., Foca , F., Masino , A., Antonelli , A., Ulrici
In the present paper, the possibility to use the information contained in RGB digital images to gain a fast and inexpensive quantification of colour-related properties of food is explored. To this aim, we present an approach which consists, as first step, in condensing the colour related information contained in RGB digital images of the analysed samples in one-dimensional signals, named colourgrams. These signals are then used as descriptor variables in multivariate calibration models. The feasibility of this approach has been tested using as a benchmark a series of samples of pesto sauce, whose RGB images have been used to predict...

Graphical abstract

 Graphical abstract:  Highlights: ► Visual aspect of a sample can be quantified by RGB images ► Colour-related information is codified in the form of a signal named colourgram ► Colourgrams are used to build multivariate calibration/feature selection models ► Sensory and compositional characteristics of samples (e.g. food) can be predicted ► Reconstruction of selected features as images allow direct and easy interpretation
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Aptamer Enzymatic Cleavage Protection Assay for the Gold Nanoparticle-Based Colorimetric Sensing of Small Molecules

08 September 2011, 20:28:21Go to full article
Publication year: 2011
Source: Analytica Chimica Acta, In Press, Accepted Manuscript, Available online 7 September 2011
Valérie, Guieu , Corinne, Ravelet , Sandrine, Perrier , Zhenyu, Zhu , Simon, Cayez , ...
A label-free, homogeneous aptamer-based sensor strategy was designed for the facile colorimetric detection of small target molecules. The format relied on the target-induced protection of DNA aptamer from the enzymatic digestion and its transduction into a detectable signal through the length-dependent adsorption of single-stranded DNA onto unmodified gold nanoparticles (AuNPs). The proof-of-principle of the approach was established by employing the anti-tyrosinamide aptamer as a model functional nucleic acid. In the absence of target, the aptamer was cleaved by the phosphodiesterase I enzymatic probe, leading to the release of mononucleotides and short DNA fragments. These governed effective electrostatic stabilization of AuNPs...

Graphical abstract

 Graphical abstract:  Highlights: ► Homogeneous aptasensor designed for colorimetric detection of small molecules. ► Format relied on target-induced protection of aptamer from enzymatic digestion. ► Transduction attained through adsorption of DNA onto gold nanoparticles. ► Sensing platform successfully applied to tyrosinamide and adenosine detection.
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A strategy for constructing sensitive and renewable molecularly imprinted electrochemical sensors for melamine detection

08 September 2011, 20:28:21Go to full article
Publication year: 2011
Source: Analytica Chimica Acta, In Press, Accepted Manuscript, Available online 7 September 2011
Jianping, Li , Zhiqiang, Chen , Yuping, Li
A novel strategy for preparing highly sensitive and easily renewable molecularly imprinted polymer (MIP) sensors was proposed. Using melamine (MA) as the template molecule, MIP particles were synthesized and embedded in a solid paraffin carbon paste to prepare the MIP sensor. MA was indirectly determined from the competition between the reactions of MA and horseradish peroxidase-labeled MA (MA-HRP) with the vacant cavities. The detection signals were amplified because of enzymatic reaction to the H2O2 catalytic oxidation. Sensitivity was markedly improved. Sensor renewal was achieved by a simple mechanical polishing of the sensitive film. The linear range for MA detection was...

Graphical abstract

 Graphical abstract: A strategy for preparing molecularly imprinted electrochemical sensors with a highly sensitive and easily renewable film is proposed. Film renewability was achieved by embedding MIP particles in a solid paraffin carbon paste, and the high sensitivity was detected using a highly sensitive enzyme amplifier. Highlights: ► A strategy for preparing molecularly imprinted electrochemical sensors with a highly sensitive and easily renewable film is proposed. ► MIP particles were synthesized and embedded in a solid paraffin carbon paste to prepare the MIP sensor. ► The detection signals were amplified because of enzymatic reaction to the H2O2 catalytic oxidation. ► Sensitive film renewability was achieved by embedding MIP particles in a solid paraffin carbon paste. ► Melamine was selected as the template moleculeimage

Thursday, 8 September 2011

Just Published: Trends in Analytical Chemistry

A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:
Selected papers from the latest issue:

Ionic liquids as a tool for determination of metals and organic compounds in food analysis

23 August 2011, 22:31:50Go to full article
Publication year: 2011
Source: TrAC Trends in Analytical Chemistry, In Press, Accepted Manuscript, Available online 23 August 2011
Aurora, Martín-Calero , Verónica, Pino , Ana M., Afonso
Ionic liquids (ILs) are non-molecular solvents, which are mainly characterized as possessing low melting points, low-to-negligible vapor pressures, and high thermal stability. Their unique solvation properties, coupled to the fact that they can be structurally tailored for specific applications, have increased study of ILs in many areas of fundamental and applied chemistry. Thus, ILs have successfully been utilized as novel solvents in different extraction and microextraction schemes in recent years, but mainly with environmental samples.Food samples are quite complicated matrices from an analytical point of view. They contain a large range of chemical substances, and sometimes they also have a...

Lab-on-valve in the miniaturization of analytical systems and sample processing for metal analysis

23 August 2011, 22:31:50Go to full article
Publication year: 2011
Source: TrAC Trends in Analytical Chemistry, In Press, Accepted Manuscript, Available online 23 August 2011
Yong-Liang, Yu , Ying, Jiang , Ming-Li, Chen , Jian-Hua, Wang
In the past decade, the lab-on-valve (LOV) system, as the third-generation of the flow-injection (FI) analysis technique, has exhibited powerful capability in instrument miniaturization and on-line sample pretreatment.This review presents and discusses the state of the art in the progress of the LOV system in the determination of metal species in two parts:miniaturization of analytical instrumentation; and,sample-processing front-ends.As a miniaturized analytical set-up, LOV incorporates detection techniques for the determination of metal species (e.g., spectrophotometry, electrochemical detection and atomic spectrometry). However, coupling LOV sample pretreatment with atomic or mass spectrometric detectors provides high-sensitivity determination or speciation of metal species.We also discuss...

Flexible, High Performance Solvent Evaporators

HT Series II Solvent Evaporators from Genevac offer leading edge features that provide superior sample protection, flexibility for multiple applications, consistency of results, robust build quality, ease-of-use, rapid high-throughput results and low maintenance.

A new pdf brochure (www.genevac.com/en/NewsPg.asp?S=6&V=1&Page=95) provides detailed information for all current products ranging from the compact HT-4X that sets the standard for bench-top solvent evaporation to the HT-8, HT-12 and HT-24, the pinnacle of very high throughput evaporator technology.
 
Each product section comprises technical description and basic specifications, photograph of the system, available options and key feature / benefits.  Further information is provided on Genevac's wide range of sample holders, intuitive yet powerful software and options for fast lyophilisation and specialist applications including handling highly volatile, explosive or acidic samples.  A selection guide helps you to select the most appropriate HT system for your application.
 
Technology at a glance features describe HT-Series innovations including Dri-Pure® that eliminates the unwanted effects of solvent bumping; SampleGuard™ that prevents heat damage to samples while ensuring rapid evaporation and Auto-Defrost & Drain that enables volatile solvents to be collected and safely disposed of.

For further information please contact Genevac now on telephone +44-1473-240000 / +1-845-255-5000 or email salesinfo@genevac.co.uk

Wednesday, 7 September 2011

Just Published: Journal of Chromatography B

A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:
Selected papers from the latest issue:

MCX based solid phase extraction combined with liquid chromatography tandem mass spectrometry for the simultaneous determination of 31 endocrine-disrupting compounds in surface water of Shanghai

04 September 2011, 20:14:09Go to full article
Publication year: 2011
Source: Journal of Chromatography B, In Press, Accepted Manuscript, Available online 3 September 2011
Hong-Chang, Zhang , Xue-jun, Yu , Wen-chao, Yang , Jin-feng, Peng , Ting, Xu , ...
A novel analytical method employing MCX (mixed-mode cationic exchange) based solid phase extraction (SPE) coupled with liquid chromatography tandom mass spectrometry (LC-MS/MS) was developed to detect 31 endocrine-disrupting compounds (EDCs) in surface water samples simultaneously. The target EDCs belong to five classes, including seven estrogens, eight androgens, six progesterones, five adrenocortical hormones and five industrial compounds. In order to simultaneously concentrate the target EDCs and eliminate matrix interferences in the water samples, MCX SPE cartridges were employed for SPE, and then followed by a simple and highly efficient three-step sequential elution procedure. Two electrospray ionization (ESI) detection modes, positive (ESI+)...

A New Strategy for the On-column Exopeptidase Cleavage of Poly-Histidine Tagged Proteins

04 September 2011, 20:14:09Go to full article
Publication year: 2011
Source: Journal of Chromatography B, In Press, Accepted Manuscript, Available online 3 September 2011
Wen-Hui K., Kuo , Howard A., Chase
This paper describes a new strategy, which aims to make on-column poly-histidine tag removal more useful in the production of recombinant proteins by improving the yield and efficiency of on-column exopeptidase cleavage. This involves improvement of the on-column cleavage condition by using imidazole concentrations in the range of 100mM to 500mM in the cleavage buffer. At 300mM imidazole, maximum on-column cleavage yield (in excess of 99%) was achieved in 3hours of incubation. However, as a result of the increased imidazole concentration, this new strategy of on-column cleavage results in some residual uncleaved poly-histidine tagged proteins (∼0.1%) and the production of...
 Highlights: ► A new strategy to improve the yield and efficiency of on-column exopeptidase cleavage is described. ► Maximum on-column cleavage yield in excess of 99% was achieved in 3hours of incubation at 300mM imidazole. ► The effect of protease concentration and incubation time on the new strategy is significant. ► Comparisons are made for different tag removal strategies.

Fabrication of a novel nanocomposite based on sol–gel process for hollow fiber–solid phase microextraction of aflatoxins;B1 and B2, in cereals combined with high performane liquid chromatography- diode array detection

04 September 2011, 20:14:09Go to full article
Publication year: 2011
Source: Journal of Chromatography B, In Press, Accepted Manuscript, Available online 3 September 2011
Zarrin, Es’haghi , Hoda, Sorayaei , Fateme, Samadi , Mahboubeh, Masrournia , Zohreh, Bakherad
The new pre-concentration technique, hollow fiber-solid phase microextraction based on carbon nanotube reinforced sol-gel and liquid chromatography-photodiode array detection was applied to determination of aflatoxins B1,B2 (AFB1, AFB2) in rice, peanut and wheat samples. This research provides an overview of trends related to synthesis of solid phase microextraction (SPME) sorbnents that improves the assay of aflatoxins as the semi-polar compounds in several real samples. It mainly includes summary and a list of the results for a simple carbon nanotube reinforced sol-gel in-fiber device. This device was used for extraction, pre-concentration and determination of aflatoxins B1,B2 in real samples. In this...

Just Published: Journal of Chromatography A

A new issue of this journal has just been published. To see abstracts of the papers it contains (with links through to the full papers) click here:
Selected papers from the latest issue:

Multipesticide residue analysis in maize combining acetonitrile-based extraction with dispersive liquid-liquid microextraction followed by gas chromatography-mass spectrometry

06 September 2011, 23:21:50Go to full article
Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 6 September 2011
S.C., Cunha , J.O., Fernandes
A fast and simple gas chromatography-mass spectrometry (GC-MS) method for determination of forty-one pesticides residues in maize is introduced. The sample preparation involves liquid-liquid partitioning with acetonitrile in presence of anhydrous MgSO4 and NaCl (QuEChERS) followed by dispersive liquid-liquid microextraction (DLLME) using carbon tetrachloride as extractive solvent and the extract obtained by QuEChERS as dispersive solvent. The main factors influencing DLLME efficiency including extractive solvent type and volume as well as the volume of dispersive solvent were evaluated in this study. The DLLME procedure effectively provides an enrichment of the extract and a cleanup of certain polar matrix components, which...

SEC-Gradients, an alternative approach to polymer gradient chromatography: 2. Separation of Poly(meth)acrylates using a SEC-solvent/non-solvent gradient

06 September 2011, 23:21:50Go to full article
Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 6 September 2011
Martin, Schollenberger , Wolfgang, Radke
A gradient ranging from methanol to tetrahydrofuran (THF) was applied to a series of poly(methyl methacrylate) (PMMA) standards, using the recently developed concept of SEC gradients. Contrasting to conventional gradients the samples eluted before the solvent, i.e. within the elution range typical for separations by SEC, however, the high molar mass PMMAs were retarded as compared to experiments on the same column using pure THF as the eluent. The molar mass dependence on retention volume showed a complex behaviour with a nearly molar mass independent elution for high molar masses. This molar mass dependence was explained in terms of solubility...
 Highlights: ► The recently developed method of SEC-gradients was applied to the separation of poly(meth)acrylate blends. ► Separations of blends of PMMA and PtBA, respectively PMMA and PnBA were achieved in SEC gradients running from Methanol to THF ► The comparison of the eluent compositions at elution with cloud point measurements suggest that the separation is based on dissolution/precipitation.

Rapid and simultaneous determination of hexa peptides (Ac-EEMQRR-amide and H2N-EEMQRR-amide) in anti-wrinkle cosmetics by hydrophilic interaction liquid chromatography - solid phase extraction preparation and hydrophilic interaction liquid chromatography with tandem mass spectrometry

06 September 2011, 23:21:50Go to full article
Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 6 September 2011
Wanlong, Zhou , Perry G., Wang , Alexander J., Krynitsky , Jeanne I., Rader
A rapid method for the simultaneous determination of Ac-EEMQRR-amide and H2N-EEMQRR-amide in cosmetic products was developed and evaluated. This analytical procedure involved extracting samples with 0.1:0.1:85:15 (v:v) trifluoroacetic acid (TFA):formic acid:acetonitrile (ACN):water and determination by hydrophilic interaction liquid chromatography with tandem mass spectrometry (HILIC-MS/MS). Samples showing serious ion suppression were further cleaned up using HILIC-SPE prior to HILIC-MS/MS analysis. Stable isotopically labeled peptides, corresponding to the above two peptides, were used as internal standards to correct for loss of recovery and matrix effects. Electrospray ionization (ESI) in the positive mode was used. The linear range was 2.0 - 1000ng/mL for...
 Highlights: ► A rapid method for the simultaneous determination of Ac-EEMQRR-amide and H2N-EEMQRR-amide in cosmetic products ► Ac-EEMQRR-amide is an anti-aging/anti-wrinkle agent widely used in cosmetics. ► No methodology has previously been reported to quantitate these agents in cosmetic preparations and other products. ► This is the first paper using HILIC-SPE for preparation, analytical HILIC column for separation, and tandem mass spectrometry (MS/MS) with isotopically labeled internal standards for quantitation of peptides in cosmetic products. ► This method has been evaluated and successfully applied to several cosmetics products and may also be applicable for determination of peptides in other products.

Randox Food Diagnostics release multi-analyte Anthelmintics Testing Platform

Randox Food Diagnostics is pleased to announce the release of an Anthelmintics testing platform (EV3770). This multi-analyte testing array is used in conjunction with the patented Randox Biochip Array Technology and Evidence Investigator analyser. The extensive test menu includes Avermectins, Benzimidazoles, Amino–benzimidazoles, Levamisole, Thiabendazole, Moxidectin and Triclabendazole.

Anthelmintics are drugs that act against internal parasites of animals such as tapeworms, liver flukes and round worms that can cause helminthic infections. The use of Anthelmintic drugs can greatly improve livestock production; however, effective monitoring is required to ensure residues are not passed into the human food chain.

Due to the excellent generic nature of our in house developed antibodies, the Anthelmintics Array can detect 25 analytes in total. Both parent and metabolite forms of the most commonly abused anthlemintic compounds can be detected. These include albendazole sulphoxide and albendazole – 2 aminosulphones that are the main residues detected in tissue matrices irrespective of whether animals were dosed with netobimim, albendazole or albendazole sulphoxide. The generic Avermectin biochip can detect residues of Ivermectin, Abamectin, Doramectin, Emamectin benzoate and Eprimomectin, all or some of which have been noted as marker residues in food by the European Union, CODEX, Canada and the United States of America.

Excellent limits of detection are achieved in milk (0.05 – 3ppb) and in beef muscle (0.15 – 6.5ppb) ensuring compliance with most regulatory tolerance requirements is achieved. Using this unique multi-analyte testing platform will reduce time and labour, significantly increasing sample throughput.
                                                                       
Please visit our website for more information: http://www.randoxfooddiagnostics.com/ or email enquiries@randoxfooddiagnostics.com

Tuesday, 6 September 2011

International Symposium on Analytical and Applied Pyrolysis

After a break of 4 years the Institut für Chemische Technologie Organischer Stoffe Johannes Kepler Universität Linz will be holding an International Symposium on Analytical and Applied Pyrolysis. So please save the date:
when:   May, 21st - 25th 2012
where:  Linz, Austria
please check our website www.pyrolysis2012.com which will provide all necessary information very soon.